OAI/Geometry/RCD/Metric/EuclideanGreenIdentity.lean

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4 declarations, 0 contain sorry, 0 declared as axioms

Compact-test Green identity in Euclidean space

  1. theorem OAI.RegularPointCoordinates.integral_second_directional_commute line 16

    Source documentation

    Two integrations by parts move a second directional derivative to its compactly supported test function.

    theorem integral_second_directional_commute {n : ℕ} {f g : Euclidean n → ℝ}
        (hf : ContDiff ℝ 2 f) (hg : ContDiff ℝ 2 g) (hgs : HasCompactSupport g)
        (v : Euclidean n) :
        (∫ x, f x*fderiv ℝ (fun y => fderiv ℝ g y v) x v) =
          ∫ x, fderiv ℝ (fun y => fderiv ℝ f y v) x v*g x := by
    …

    Mentions: OAI.RegularPointCoordinates.Euclidean

  2. theorem OAI.RegularPointCoordinates.integral_directional_pairing line 49

    Source documentation

    A first-order gradient pairing against a compact test equals the negative second directional pairing.

    theorem integral_directional_pairing {n : ℕ} {f g : Euclidean n → ℝ}
        (hf : ContDiff ℝ 2 f) (hg : ContDiff ℝ 1 g) (hgs : HasCompactSupport g)
        (v : Euclidean n) :
        (∫ x, fderiv ℝ f x v*fderiv ℝ g x v) =
          -∫ x, fderiv ℝ (fun y => fderiv ℝ f y v) x v*g x := by
    …

    Mentions: OAI.RegularPointCoordinates.Euclidean

  3. theorem OAI.RegularPointCoordinates.laplacian_eq_sum_second_directional line 68

    Source documentation

    The coordinate trace of the actual second derivative.

    theorem laplacian_eq_sum_second_directional {n : ℕ} {f : Euclidean n → ℝ}
        (hf : ContDiff ℝ 2 f) :
        Δ f = fun x => ∑ i : Fin n,
          fderiv ℝ (fun y => fderiv ℝ f y (EuclideanSpace.single i 1)) x (EuclideanSpace.single i 1) := by
    …

    Mentions: OAI.RegularPointCoordinates.Euclidean

  4. theorem OAI.RegularPointCoordinates.integral_laplacian_commute line 82

    Source documentation

    Green's identity with no boundary term for a compact test.

    theorem integral_laplacian_commute {n : ℕ} {f g : Euclidean n → ℝ}
        (hf : ContDiff ℝ 2 f) (hg : ContDiff ℝ 2 g) (hgs : HasCompactSupport g) :
        (∫ x, f x*(Δ g) x) = ∫ x, (Δ f) x*g x := by
    …

    Mentions: OAI.RegularPointCoordinates.Euclidean